Magnetizing current based control of resonant converters

• US 9,559,602 B2
• Filed: 02/26/2015
• Issued: 01/31/2017
• Est. Priority Date: 02/26/2015
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Deboy, Gerald
• Primary Examiner(s): Dole, Timothy J
• Assistant Examiner(s): AHMED, YUSEF A
• Application Number:
  US14/632,664
• Publication Number:
  US 20160254755A1
• Time in Patent Office: 705 Days
• US Class Current: 1/1
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 3/33546 with automatic control of the output voltage or current H02M3/33561 takes precedence
• CPC Class Codes: H02M 3/33584 Bidirectional converters
• CPC Class Codes: H03K 17/04106 in field-effect transistor switches H03K17/0412, H03K17/0416 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A resonant converter is described that includes at least one power switch. The at least one power switch is characterized by a non-linearity coefficient that is less than or equal to a first threshold and a figure-of-merit that is less than or equal to a second threshold. The figure-of-merit being associated with an on-resistance of the at least one power switch and an output charge of the at least one power switch.

Claims

1. A resonant converter comprising:

at least one power switch that configures the resonant converter to continuously maintain a regulation span of an output voltage of the resonant converter, wherein;

the at least one power switch configures the resonant converter to continuously maintain the regulation span of the output voltage based at least in part on being characterized by a non-linearity coefficient that is less than or equal to a first threshold and a figure-of-merit that is less than or equal to a second threshold,

the non-linearity coefficient defines an amount of deviation in a rate of change of a voltage across the at least one power switch, as compared to a linear rate of change, when regulating the output voltage,

the figure-of-merit defines a product between an on-resistance of the at least one power switch and an output charge of the at least one power switch when regulating the output voltage,

the first threshold depends on a switching frequency of the resonant converter and is less than or equal to five, and

the second threshold depends on a magnetizing current associated with the resonant converter and is less than or equal to eight ohm*nano coulomb.

2. The resonant converter of claim 1, wherein the resonant converter comprises a non-isolating resonant converter that does not include a transformer.

3. The resonant converter of claim 1, wherein the resonant converter comprises an isolating resonant converter that includes a transformer.

4. The resonant converter of claim 1, wherein the at least one power switch is a normally-off Gallium Nitride (GaN) high-electron-mobility transistor (HEMT).

5. The resonant converter of claim 1, wherein the non-linearity coefficient further configures the resonant converter to continuously maintain the regulation span of the output voltage based at least in part on being less than or equal to the first threshold when the at least one power switch blocks the voltage across the at least one power switch when the voltage across the at least one power switch is between approximately ten percent to one hundred percent of a mid-voltage of the at least one power switch, the mid-voltage being one third of a rated blocking voltage of the at least one power switch.

6. The resonant converter of claim 1, wherein the non-linearity coefficient further configures the resonant converter to continuously maintain the regulation span of the output voltage based at least in part on being less than or equal to the first threshold when the at least one power switch blocks the voltage across the at least one power switch when the voltage across the at least one power switch is between approximately twenty percent to one hundred percent of a mid-voltage of the at least one power switch, the mid-voltage being one third of a rated blocking voltage of the at least one power switch.

7. The resonant converter of claim 1, wherein the first threshold is equal to five.

8. The resonant converter of claim 7, wherein the first threshold is equal to three.

9. The resonant converter of claim 8, wherein the first threshold is equal to two.

10. The resonant converter of claim 1, wherein the second threshold is equal to 8 ohm*nano coulomb.

11. The resonant converter of claim 1, wherein the second threshold is equal to 6 ohm*nano coulomb.

12. The resonant converter of claim 1, wherein the resonant converter is an inductor-inductor-capacitor (LLC) type resonant converter.

13. The resonant converter of claim 1, wherein the resonant converter is a phase shift zero voltage switching type resonant converter.

14. The resonant converter of claim 1, wherein the resonant converter is a triangle current mode (TCM) boost type resonant converter.

15. The resonant converter of claim 1, wherein:

the figure-of-merit is a first figure-of-merit;

the product is a first product;

the at least one power switch configures the resonant converter to continuously maintain the regulation span of the output voltage based at least in part on being further characterized by a second figure-of-merit that is less than or equal to a third threshold;

the second figure-of-merit defines a second product between the on-resistance of the at least one power switch and an output energy of the at least one power switch; and

the third threshold depends on a magnetizing current associated with the resonant converter and is less than or equal to eight tenths ohm*micro joule.

16. The resonant converter of claim 15, wherein the third threshold is equal to eight tenths ohm*micro joule.

17. The resonant converter of claim 15, wherein the third threshold is equal to four tenths ohm*micro joule.

18. The resonant converter of claim 1, wherein the at least one power switch comprises two power switches arranged in a half-bridge configuration and the non-linearity coefficient is an effective non-linearity coefficient measured at a switching node of the half-bridge configuration.

19. The resonant converter of claim 1, wherein the at least one power switch comprises four power switches arranged in two parallel half-bridge configurations and the non-linearity coefficient is an effective non-linearity coefficient measured at an output of the two half-bridge configurations.

20. The resonant converter of claim 1, wherein the at least one power switch comprises at least one wide band gap type device.

21. The resonant converter of claim 20, wherein the at least one power switch comprises at least one Gallium Nitride (GaN) high-electron-mobility-transistor.

22. The resonant converter of claim 21, wherein the first threshold is less than two when the voltage across the at least one power switch is approximately ten volts.

23. A power circuit comprising:

a resonant converter that includes at least one half-bridge that configures the resonant converter to continuously maintain a regulation span of an output voltage of the resonant converter, wherein;

the at least one half-bridge configures the resonant converter to continuously maintain the regulation span of the output voltage based at least in part on being characterized by having an effective non-linearity coefficient that is less than or equal to a first threshold and a figure-of-merit that is less than or equal to a second threshold,

the non-linearity coefficient defines an amount of deviation in a rate of change of a voltage across the at least one half-bridge, as compared to a linear rate of change, when regulating the output voltage,

the figure-of-merit defines a product between an on-resistance of the at least one half-bridge and an output charge of the at least one half-bridge when regulating the output voltage,

the first threshold depends on a required switching frequency of the resonant converter and is less than or equal to five, and

the second threshold depends on a required magnetizing current associated with the resonant converter and is less than or equal to eight ohm*nano coulomb.

24. A system comprising:

a power source configured to provide power;

a controller unit;

a load configured to receive the power; and

a resonant converter configured to convert the power for the load, the resonant converter includes at least one half-bridge, wherein;

the at least one half bridge is controlled by the controller unit;

the at least one half bridge configures the resonant converter to continuously maintain a regulation span of an output voltage of the resonant converter based at least in part on being characterized by having an effective non-linearity coefficient that is less than or equal to a first threshold and a figure-of-merit that is less than or equal to a second threshold,

the non-linearity coefficient defines an amount of deviation in a rate of change of a voltage across the at least one half-bridge, as compared to a linear rate of change, when regulating the output voltage,

the figure-of-merit defines a product between an on-resistance of the at least one half-bridge and an output charge of the at least one half-bridge when regulating the output voltage,

the first threshold depends on a required switching frequency of the resonant converter and is less than or equal to five, and

the second threshold depends on a required magnetizing current associated with the resonant converter and is less than or equal to eight ohm*nano coulomb.